Primitive contractions of Calabi-Yau threefolds I

Grzegorz Kapustka; Michal Kapustka

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Primitive contractions of Calabi-Yau threefolds I

Grzegorz Kapustka·Michal Kapustka

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Abstract

We construct examples of primitive contractions of Calabi--Yau threefolds with exceptional locus being $ \mathbb{P}^1 \times \mathbb{P}^1$, $\mathbb{P}^2$, and smooth del Pezzo surfaces of degrees $\leq 5$. We describe the images of these primitive contractions and find their smoothing families. In particular, we give a method to compute the Hodge numbers of a generic fiber of the smoothing family of each Calabi--Yau threefold with one isolated singularity obtained after a primitive contraction of type II. As an application, we get examples of natural conifold transitions between some families of Calabi--Yau threefolds.

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Grzegorz Kapustka, Michal Kapustka. 2008-01-24. Primitive contractions of Calabi-Yau threefolds I. https://arxiv.org/abs/math/0703810

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